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How to change the order of DataFrame columns?
...n [6]: df
Out[6]:
0 1 2 3 4 mean
0 0.445598 0.173835 0.343415 0.682252 0.582616 0.445543
1 0.881592 0.696942 0.702232 0.696724 0.373551 0.670208
2 0.662527 0.955193 0.131016 0.609548 0.804694 0.632596
3 0.260919 0.783467 0.593433 0...
Why does C# forbid generic attribute types?
...therwise required, get benefits of polymorphism etc.
//an interface which means it can't have its own implementation.
//You might need to use extension methods on this interface for that.
public interface ValidatesAttribute<T>
{
T Value { get; } //or whatever that is
bool IsValid { g...
What are the advantages of using a schema-free database like MongoDB compared to a relational databa
... a rich data structure capable of holding arrays and other documents. This means you can often represent in a single entity a construct that would require several tables to properly represent in a relational db. This is especially useful if your data is immutable.
Deep query-ability. MongoDB support...
How to get HTML 5 input type=“date” working in Firefox and/or IE 10
...r every new input type. They are better defined, and native, which usually means fast.
– Tomáš Zato - Reinstate Monica
Oct 23 '15 at 22:36
5
...
What does it mean if a Python object is “subscriptable” or not?
...
It basically means that the object implements the __getitem__() method. In other words, it describes objects that are "containers", meaning they contain other objects. This includes strings, lists, tuples, and dictionaries.
...
Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
...nt] is a subtype of List[AnyVal] because Int is a subtype of AnyVal. This means that you may provide an instance of List[Int] when a value of type List[AnyVal] is expected. This is really a very intuitive way for generics to work, but it turns out that it is unsound (breaks the type system) when u...
Covariance, Invariance and Contravariance explained in plain English?
...es, f is a type transformation, and ≤ the subtype relation (i.e. A ≤ B means that A is a subtype of B), we have
f is covariant if A ≤ B implies that f(A) ≤ f(B)
f is contravariant if A ≤ B implies that f(B) ≤ f(A)
f is invariant if neither of the above holds
Let's consider an example...
What is the wix 'KeyPath' attribute?
...Installer uses to determine if a
Component "exists" on a machine.
This means that when Windows Installer decides whether to install your component, it will first look whether the keypath resource is already present. If it is, none of the resources in the component are installed.
The presence of...
What is Pseudo TTY-Allocation? (SSH and Github)
... including SCP, SSH, Telnet and rlogin.
The name "PuTTY" has no definitive meaning, though "tty" is the name for a terminal in the Unix tradition, usually held to be short for Teletype.
Other use-cases for -T (beside testing)
Transferring binary files
Execute commands on a remote server
SSH tun...
What is WEB-INF used for in a Java EE web application?
...letContext, and may
be exposed using the RequestDispatcher calls.
This means that WEB-INF resources are accessible to the resource loader of your Web-Application and not directly visible for the public.
This is why a lot of projects put their resources like JSP files, JARs/libraries and their ...